Wireless antenna array system architecture and methods to achieve 3d beam coverage

ABSTRACT

Embodiments of wireless antenna array systems to achieve three-dimensional beam coverage are described herein. Other embodiments may be described and claimed.

REFERENCE TO RELATED INVENTIONS

The present application claims priority to U.S. patent application Ser.No. 12/888,645 titled “Wireless Antenna Array System Architecture andMethods to Achieve 3D Beam Coverage” filed Sep. 23, 2010, which is acontinuation of U.S. patent application Ser. No. 12/215,542 filed Jun.27, 2008, the entire disclosure of which is hereby incorporated byreference in its entirety.

FIELD OF THE INVENTION

The field of invention relates generally to a wireless antenna arraysystem and more specifically but not exclusively relates to a wirelesssystem architecture for transmitting and receiving millimeter-wave(mm-wave) signals in WPAN/WLAN environments.

BACKGROUND INFORMATION

Technological developments permit digitization and compression of largeamounts of voice, video, imaging, and data information. The need totransfer data between devices in wireless mobile radio communicationrequires reception of an accurate data stream at a high data rate. Itwould be advantageous to provide antennas that allow radios to handlethe increased capacity while providing an improved quality that achievesantenna coverage in both azimuth and elevation. It would also beadvantageous to provide mobile internet devices and/or access pointswith a smaller form factor that incorporates integrated, compact, highperformance antennas.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and not as alimitation in the figures of the accompanying drawings, in which:

FIG. 1 is a block diagram illustrating devices using extremely highfrequency radio signals to communicate in a wireless network.

FIG. 2 is a top view of a wireless antenna array assembly to achievethree-dimensional (3D) beam coverage using extremely high frequencyradio signals in accordance with some embodiments of the presentinvention.

FIG. 3 is a cross-sectional illustration of the wireless antenna arrayassembly of FIG. 2.

FIG. 4 is an isometric drawing of the wireless antenna array assembly ofFIG. 2.

FIG. 5 is an illustration of azimuth beam coverage of a wireless antennaarray assembly in accordance with some embodiments of the presentinvention.

FIG. 6 is an illustration of elevation beam coverage of a wirelessantenna array assembly in accordance with some embodiments of thepresent invention.

FIG. 7 is an illustration of elevation and azimuth beam coverage of atop and bottom wireless antenna array assembly in accordance with someembodiments of the present invention.

DETAILED DESCRIPTION

In the following detailed description, numerous specific details are setforth in order to provide a thorough understanding of the invention.However, it will be understood by those skilled in the art that thepresent invention may be practiced without these specific details. Inother instances, well-known methods, procedures, components and circuitshave not been described in detail so as not to obscure the presentinvention.

Embodiments of methods and systems for using wireless antenna arraysystem architecture to achieve three-dimensional (3D) beam coverage aredescribed herein. In the following description, numerous specificdetails are set forth such as a description of an arrangement of phasedand sectorized antenna arrays for achieving antenna coverage in bothazimuth and elevation to provide a thorough understanding of embodimentsof the invention. One skilled in the relevant art will recognize,however, that the invention can be practiced without one or more of thespecific details, or with other methods, components, materials, etc. Inother instances, well-known structures, materials, or operations are notshown or described in detail to avoid obscuring aspects of theinvention.

It would be an advance in the art to increase coverage for low costmillimeter wave (mm-wave) wireless devices designed to operate usinglocal area network (WLAN) and wireless personal area network (WPAN)technologies. MM-wave communication is desirable for relatively highcommunications throughput while providing high frequency reusepotential. Existing mm-wave communication techniques and systems thatemploy beam-steered or phased array antennas fail to provide a compactlow cost solution for devices that communicate using extremely highfrequency radio signals in both azimuth and elevation. Antennas designedto communicate using extremely high frequency radio signals with smallwavelengths may be designed using modest sized packages due to a smallbeam width, allowing for compact antenna array architecture. Providing alow cost and compact antenna array capable of operating using extremelyhigh frequency radio signals, for example an unlicensed short rangefrequency band with data throughputs up to 2.5 gigabit per second, inboth azimuth and elevation, would enable more efficient form factordesign of access point or consumer devices while providing increasedoperability in a variety of applications. As a result, directionallimiting communication capability inherent to existing antenna types areavoided and access points or devices employing extremely high frequencyradio signals in a high bandwidth wireless communication environment mayenjoy multidirectional wireless coverage from a low-cost, yet compactantenna array system.

Embodiments of 60 GHz band ((57-66 GHz) millimeter-wave (mm-wave)communications devices may be used in a variety of applications. Someembodiments of the invention may be used in conjunction with variousdevices and systems, for example, a transmitter, a receiver, atransceiver, a transmitter-receiver, a wireless communication station, awireless communication device, a wireless Access Point (AP), a modem, awireless modem, a Personal Computer (PC), a desktop computer, a mobilecomputer, a laptop computer, a notebook computer, a tablet computer, aserver computer, a set-top box, a handheld computer, a handheld device,a Personal Digital Assistant (PDA) device, a handheld PDA device, amobile station (MS), a graphics display, a communication station, anetwork, a wireless network, a Local Area Network (LAN), a Wireless LAN(WLAN), a Metropolitan Area Network (MAN), a Wireless MAN (WMAN), a WideArea Network (WAN), a Wireless WAN (WWAN), devices and/or networksoperating in accordance with existing IEEE 802.11, 802.11a, 802.11b,802.11e, 802.11g, 802.11 h, 802.11i, 802.11n, 802.16, 802.16d, 802.16estandards and/or future versions and/or derivatives and/or Long TermEvolution (LTE) of the above standards, a Personal Area Network (PAN), aWireless PAN (WPAN), units and/or devices which are part of the aboveWLAN and/or PAN and/or WPAN networks, one way and/or two-way radiocommunication systems, cellular radio-telephone communication systems, acellular telephone, a wireless telephone, a Personal CommunicationSystems (PCS) device, a PDA device which incorporates a wirelesscommunication device, a Multiple Input Multiple Output (MIMO)transceiver or device, a Single Input Multiple Output (SIMO) transceiveror device, a Multiple Input Single Output (MISO) transceiver or device,a Multi Receiver Chain (MRC) transceiver or device, a transceiver ordevice having “smart antenna” technology or multiple antenna technology,or the like. Some embodiments of the invention may be used inconjunction with one or more types of wireless communication signalsand/or systems, for example, Radio Frequency (RF), Infra Red (IR),Frequency-Division Multiplexing (FDM), Orthogonal FDM (OFDM),Time-Division Multiplexing (TDM), Time-Division Multiple Access (TDMA),Extended TDMA (E-TDMA), General Packet Radio Service (GPRS), ExtendedGPRS, Code-Division Multiple Access (CDMA), Wideband CDMA (WCDMA), CDMA2000, Multi-Carrier Modulation (MDM), Discrete Multi-Tone (DMT),Bluetooth®, ZigBee™, or the like. Embodiments of the invention may beused in various other apparatuses, devices, systems and/or networks.

Turning now to the figures, FIG. 1 is a block diagram illustratingdevices, such as access points (100 a & 100 b), mobile stations (110 a &110 b), a graphics display (120) and communication stations (130 a & 130b) using extremely high frequency radio signals to communicate in anextremely high frequency wireless network 140. Access point 100 a maycommunicate with another access point 100 b and communication stations,such as communication stations (CS) 130 a and 130 b. The CSs 130 a and130 b may be fixed or substantially fixed devices. In some embodiments,access points 100 a may use millimeter-wave signals for communicating,although the scope of the invention is not limited in this respect.Access point 100 a may also communicate with other devices such asmobile station 110 a and graphics display 120. In some embodiments,access point 100 a and mobile station 110 a operate as part of apeer-to-peer (P2P) network. In other embodiments access point 100 a andmobile station 110 a operate as part of a mesh network, in whichcommunications may include packets routed on behalf of other wirelessdevices of the mesh network, such as mobile station 110 b. Fixedwireless access, wireless local area networks, wireless personal areanetworks, portable multimedia streaming, and localized networks such asan in-vehicle networks, are some examples of applicable P2P and meshnetworks.

Devices such as the access points (100 a & 100 b), mobile stations (110a & 110 b), graphics display (120) and communication stations (130 a &130 b) may communicate using extremely high frequency radio signalstransmitted and received through a combination sectorized and phasedwireless antenna array assembly. FIG. 2 is a top view of a wirelessantenna array assembly 200 to achieve three-dimensional (3D) beamcoverage using extremely high frequency radio signals in accordance withsome embodiments of the present invention.

One or more planar antennas 210 may be affixed to a surface of a firstsubstrate 220 and configured to form a planar antenna array, whichcombined with two or more substrates including second substrate 230 (seeFIG. 4) and third substrate 240 (see FIG. 4) comprise the wirelessantenna array assembly 200. One or more planar antennas 210 may bedipole, patch, slot or any other type of mm-wave antenna elements. Thefirst substrate 220, second substrate 230, and third substrate 240(hereinafter, ‘the substrates’) are selected to be compatible in mm-waveapplications. Planar antennas 210 may be used because of their lowprofile, low cost, light weight, and their ease of integration intoplanar arrays.

The substrates may be selected from the group comprising Low TemperatureCo-fired Ceramic (LTCC), alumina (Al₂O₃), antenna grade core materialsand laminates such as Rogers Corp. RO™ series, duroid, liquid crystalpolymer (LCP), high-resistivity silicon or one or more other suitablesubstrates for mm-wave applications. The substrates may be shaped in anyvariety of shapes and sizes, for example, substantially between 1 to 50centimeters (cm) width and substantially between 50 μm and 1200 μm inthickness. In one embodiment, the substrates are all one shape, size,and thickness. Alternately, the substrates may be selectively designedto differ in shape, size, and or thickness depending on application andhow the wireless antenna array assembly 200 is designed and developed.

The first substrate 220 may be planar or substantially planar to providea platform to affix a phased array of planar antennas 210. The planarantennas 210 may be configured in a rectangular, dithered, randomized,or any combinations thereof to achieve a desired elevation beamcoverage. A phased array is a group of antennas in which the relativephases of the respective signals feeding the planar antennas 210 arevaried in such a way that an effective radiation pattern of theplanar-phased array is reinforced in a desired direction and suppressedin undesired directions. A planar array is a group of antennas in whichall of the elements are in, or are substantially in one plane. In thisembodiment, the planar-phased array of antennas provide elevation beamcoverage from the first substrate 220.

Each planar antenna 210 comprises a conductive sheet selectivelydesigned to transmit and receive wireless signals and may be formeddirectly on the first substrate 220. A design of each planar antenna 210may be developed by defining metal patterns on the substrates. Inanother embodiment, each planar antenna 210 is formed on an intermediatesubstrate which is affixed to the first substrate 220. Each planarantenna 210 may be a patch, slot, spiral, or any other suitable antennastructure to provide elevation beam coverage. One or more differenttypes of planar antennas 210 may be used to form an array on the firstsubstrate 220.

FIG. 3 is a cross-sectional illustration of the wireless antenna arrayassembly 200 of FIG. 2. The first substrate cross-section 320 is across-sectional view of the first substrate 220 through section lineA-A. Planar antennas 210 on the first substrate 220 are coupled to thesecond substrate 230 through a plurality of vias 310. In one embodiment,the vias 310 are formed of a conductive material such as copper (Cu),gold (Au), or another suitable conductive material and routed throughthe first substrate 220 through one or more channels or vias to provideradio frequency signals through the first substrate 220. In anotherembodiment, the vias 310 are selectively designed to provide efficientmm-wave interconnect routing using shielded stripline or microstrip typetransmission structures. A stripline is an electrical transmission lineused to convey extremely high frequency radio signals and is formed of aconductive material, for example one or more metals such as copper (Cu)or gold (Au), sandwiched between two ground elements such as groundplanes (not shown). A microstrip is an alternate type of electricaltransmission line. The microstrip is a conductive material formed on adielectric layer that separates the microstrip from a ground elementsuch as a ground plane (not shown).

A second substrate cross-section 330 is a cross-sectional view of thesecond substrate 230 through section line B-B. The second substrate 230is an interface structure to provide interconnect routing between thefirst substrate 220 and the third substrate 240 through one or moreinterconnects 335 while providing a recess 345 for one or more raisedfeatures on substrate 240.

A third substrate cross-section 340 is a cross-sectional view of thethird substrate 240 through section line B-B. A plurality of endfireantennas 350, such as quasi-Yagi-Uda, planar slot, and other relatedantenna patterns provide a sectorized endfire antenna array on the thirdsubstrate 240. One or more different types of endfire antennas 350 maybe used to form an array on the third substrate 240.

An integrated circuit (IC) 360 connected to the third substrate 240,using a flip-chip process or another chip attachment process known toone skilled in the art, may be formed from group III-V semiconductortechnology such as Gallium Arsenide (GaAs) and Indium Phosphide (InP).Alternately, the IC 360 may be formed from Silicon Germanium (SiGe),Heterojunction Bipolar Transistor (HBT), bipolar junction transistorscombined with complimentary metal-oxide semiconductor (BiCMOS), andsilicon technology such as complimentary metal-oxide semiconductor(CMOS). CMOS technology provides low cost and highly integratedsolutions, whereby RF building blocks, active and passive elements areintegrated on the same chip, as compared to other availabletechnologies.

One IC 360 is illustrated in this embodiment, however a plurality of ICs360 may be used in the wireless antenna array assembly 200. The IC 360is coupled to the endfire antennas 350 to provide sectorized arraycoverage and coupled to the planar antennas 210 through interconnects335 and 310 to provide phased array coverage by the wireless antennaarray assembly 200. The interconnects 335 may carry radio frequency (RF)signals from the first substrate 220, through metal-vias 310, metalbumps 355 and metal-vias 335, to the third substrate 240. Further, theIC 360 may be coupled to backend circuits and processor inputs throughvias 315 and metal bumps 355 formed in and on the third substrate 240using direct current (DC) and low frequency signals. The IC 360 may alsobe connected to the endfire antennas 350 using a plurality of microfeedlines 410. The microfeed lines 410 may be one or more patterned metallayers on a substrate, such as the third substrate 240 of FIG. 4.Additionally, the microfeed lines 410 may be formed on more than onesubstrate layer to connect the integrated circuit 360, planar antennas210, and endfire antennas 350 in the wireless antenna array assembly200.

FIG. 4 is an isometric drawing of the wireless antenna array assembly200 of FIG. 2 illustrating the first substrate 220 with the planarantennas 210 in a phased array to provide elevation coverage. The secondsubstrate 230 provides a plurality of interconnects 335 to connect thefirst substrate 220 to the third substrate 240. The third substrate 240with the integrated circuit 360 and the endfire antennas 350 in asectorized array provides azimuth coverage.

In one embodiment, the integrated circuit 360 may include a mm-wavetransceiver for processing signals received by the endfire antennas 350and/or the planar phased-array antennas 210 and for generating mm-wavesignals for transmission by the endfire antennas 350 and/or the planarbroadside antennas 210. The integrated circuit 360 may also includeprocessing circuitry which may configure the endfire antennas 350 and/orthe planar phased array antenna elements 210 for receiving and/ortransmitting in a selected direction. The processing circuitry may alsoidentify directions for communicating with other wireless devices, rankthe directions based on signal levels, and coordinate the directionalcommunications with another wireless device in one of the selecteddirections.

Three substrates are illustrated in this embodiment, however otherantenna array assembly configurations may be selectively designed withadditional substrates and antennas depending on application and beamcoverage requirements. The endfire antennas 350 may be configured in arectangular, circular, or any other shape to achieve a desired azimuthbeam coverage.

FIG. 5 depicts the wireless antenna array assembly 200 of FIG. 2 whileillustrating azimuth beam coverage from a plurality of azimuth beams500, in accordance with some embodiments of the invention. In thisembodiment, the wireless antenna array assembly 200 is configured toprovide complete azimuth beam coverage in a circular design across 360degrees. In another embodiment, the wireless antenna array assembly isconfigured in a rectangular design to achieve a desired azimuth beamcoverage, though the embodiment is not so limited.

FIG. 6 depicts the wireless antenna array assembly 200 of FIG. 2 whileillustrating azimuth and elevation beam coverage from a plurality ofazimuth beams 500 and a plurality of elevation beams 600, in accordancewith some embodiments of the invention. In this embodiment, the wirelessantenna array assembly 200 is configured to provide elevation beamcoverage across 180 degrees. In another embodiment, the wireless antennaarray assembly 200 is configured to provide less than 180 degreeelevation beam coverage, though the embodiment is not so limited. Thewireless antenna array assembly 200 comprises complementary antennatypes to provide azimuth and elevation coverage.

An amount of antenna gain will depend on the antenna topologiesselection and configuration. For wavelengths in a 60 GHz band, theantennas are a few millimeters in size single antenna gain for mm-waveapplications may range between 3-18 dBi based on antenna type selectionand configuration. Achieving more than 10-15 dBi antenna gain isnecessary for practical WPAN-type applications. A single antenna orantenna arrays and/or stacks can be fabricated on and/or attached to thesubstrates to provide higher gain values. As an example, between 4 and16 high-gain endfire antennas may be arranged upon a third substrate 240to provide desired azimuth beam coverage across 360 degrees.

FIG. 7 is an illustration of elevation and azimuth beam coverage of atop and bottom wireless antenna array assembly 700 in accordance withsome embodiments of the present invention. The top and bottom wirelessantenna array assembly 700 in this embodiment is comprised of twowireless antenna array assemblies 200 configured to provide complete 360degree azimuth coverage as well as complete 360 degree elevationcoverage. In one embodiment, the top and bottom wireless antenna arrayassembly 700 is an omnidirectional antenna to provide omnidirectionalbeam coverage over a distance of 10 meters (m).

While specific embodiments of, and examples for, the invention aredescribed herein for illustrative purposes, various equivalentmodifications are possible within the scope of the invention, as thoseskilled in the relevant art will recognize. In the description andclaims, the terms “coupled” and “connected,” along with theirderivatives, may have been used. It should be understood that theseterms are not intended as synonyms for each other. Rather, in particularembodiments, “connected” may be used to indicate that two or moreelements are in direct physical or electrical contact with each otherwhile “coupled” may further mean that two or more elements are not indirect contact with each other, but yet still co-operate or interactwith each other.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment of the present invention. Thus, theappearances of the phrases “in one embodiment” or “in an embodiment” invarious places throughout this specification are not necessarily allreferring to the same embodiment. Furthermore, the particular features,structures, or characteristics may be combined in any suitable manner inone or more embodiments.

Modifications may be made to the invention in light of the abovedetailed description. The terms used in the following claims should notbe construed to limit the invention to the specific embodimentsdisclosed in the specification and the drawings. Rather, the scope ofthe invention is to be determined entirely by the following claims,which are to be construed in accordance with established doctrines ofclaim interpretation.

1-20. (canceled)
 21. A millimeter-wave (mm-wave) communicationsassembly, comprising: a first mm-wave antenna on a first substrate,wherein the first mm-wave antenna is configured to provide antennacoverage in directions substantially perpendicular to the firstsubstrate; an second mm-wave antenna on a second substrate, wherein thesecond mm-wave antenna is configured to provide antenna coverage indirections substantially parallel to the first substrate; and anintegrated RF circuit that is flip-chip mounted to the second substratethat includes the second mm-wave antenna, wherein the integrated RFcircuit is coupled to the first and second mm-wave antennas, and whereinthe integrated RF circuit comprises a receiver, a transmitter, or atransceiver and is configured to process mm-wave signals.
 22. Themm-wave communications assembly defined in claim 21, wherein the firstmm-wave antenna comprises a broadside mm-wave antenna and wherein thesecond mm-wave antenna comprises an endfire mm-wave antenna.
 23. Themm-wave communications assembly defined in claim 21, wherein the firstand second substrates lie in respective first and second planes, whereinthe first plane is substantially parallel to the second plane; whereinthe first mm-wave antenna is configured to provide antenna coverage indirections substantially normal to the first plane, and wherein thesecond mm-wave antenna is configured to provide antenna coverage indirections substantially parallel to the second plane.
 24. The mm-wavecommunications assembly defined in claim 21, wherein the first mm-waveantenna comprises a planar patch antenna.
 25. The mm-wave communicationsassembly defined in claim 21, wherein the second mm-wave antennacomprises a Yagi antenna.
 26. The mm-wave communications assemblydefined in claim 21, wherein the second mm-wave antenna comprises a slotantenna.
 27. The mm-wave communications assembly defined in claim 21,wherein the second mm-wave antenna comprises a Vivaldi antenna.
 28. Themm-wave communications assembly defined in claim 21, wherein the secondmm-wave antenna comprises a dipole antenna.
 29. The mm-wavecommunications assembly defined in claim 21, wherein the first andsecond substrates comprise Low Temperature Co-fired Ceramic antennagrade core material.
 30. An apparatus for about 57-66 GHz band wirelesscommunication, comprising: a planar antenna on a first substrate; anendfire antenna on a second substrate; an integrated radio-frequency(RF) circuit that is flip-chip mounted to the second substrate; and aninterconnect that couples the planar antenna to the integrated RFcircuit to carry a millimeter wave (mm-wave) signal between the planarantenna and the integrated RF circuit.
 31. The apparatus defined inclaim 30, wherein the planar antenna comprises a planar patch antenna.32. The apparatus defined in claim 30, wherein the planar antenna isselected from the group consisting of: a patch antenna, slot antenna,spiral antenna, monopole antenna, and a dipole antenna.
 33. Theapparatus defined in claim 30, wherein the endfire antenna comprises anantenna selected from the group consisting of: a Yagi antenna, a slotantenna, a Vivaldi antenna, and a dipole antenna.
 34. The apparatusdefined in claim 30, wherein the endfire antenna is selected from thegroup consisting of: a quasi-Yagi-Uda antenna, slot antenna, Vivaldiantenna, dipole antenna, and low-profile-horn antenna.
 35. A wirelesscommunications assembly, comprising: a plurality of planar antennasconfigured to operate in a communications band at about 57-66 GHz; aplurality of endfire antennas configured to operate in thecommunications band at about 57-66 GHz; and an integrated RF circuitconnected to the plurality of planar antennas through a number of viasand to the plurality of endfire antenna through a number of feed lines.36. The wireless communications assembly defined in claim 35 wherein theplurality of planar antennas are together configured to at least receiveor transmit signals at about 57-66 GHz in directions substantiallynormal to a common plane.
 37. The wireless communications assemblydefined in claim 36 wherein the plurality of endfire antennas aretogether configured to at least receive or transmit signals at about57-66 GHz in directions substantially parallel to the common plane. 38.The wireless communications assembly defined in claim 37 wherein each ofthe plurality of endfire antennas is configured to at least receive ortransmit signals at about 57-66 GHz in a unique direction that issubstantially parallel to the common plane to provide antenna coveragefor the wireless communications assembly in at least an approximatesemi-circle that extends out from the wireless communications assembly.39. The wireless communications assembly defined in claim 37 whereineach of the plurality of endfire antennas is configured to at leastreceive or transmit signals at about 57-66 GHz in a unique directionthat is substantially parallel to the common plane to provide antennacoverage for the wireless communications assembly in substantially alldirections that are coplanar with the common plane.
 40. A wirelesscommunications assembly, comprising: a plurality of planar antennasconfigured to operate in a communications band at approximately 60 GHz;a plurality of endfire antennas configured to operate in thecommunications band at approximately 60 GHz; and an integrated RFcircuit connected to the plurality of planar antennas and to theplurality of endfire antennas to provide an antenna array with coveragenormal to the planar antennas and at least one direction parallel to theplanar antennas.
 41. The wireless communications assembly defined inclaim 40, wherein each of the planar antennas comprises a planar patchantenna.
 42. The wireless communications assembly defined in claim 40,wherein each of the planar antennas is selected from the groupconsisting of: a patch antenna, slot antenna, spiral antenna, monopoleantenna, and a dipole antenna.
 43. The wireless communications assemblydefined in claim 40, wherein each of the endfire antennas comprises anantenna selected from the group consisting of: a Yagi antenna, a slotantenna, a Vivaldi antenna, and a dipole antenna.
 44. The wirelesscommunications assembly defined in claim 40, wherein each of the endfireantennas is selected from the group consisting of: a quasi-Yagi-Udaantenna, slot antenna, Vivaldi antenna, dipole antenna, andlow-profile-horn antenna.